Answer:
Cr 6+ & SO4 2-
Explanation:
Sulfate is a polyatomic ion that has a charge of 2-. There are three of them in the chemical formula so it equates to a 6- total charge. Thus, chromium must have a 6+ charge to give the compound a neutral charge.
Answer: A
Explanation:
This means that the atomic number decreases by 1 but the mass remains constant, meaning the atomic number of the new element is 20. This corresponds to calcium.
Answer:
They are clumped together and fluffy looking
Explanation:
I’ve seen what they looked like in a project during highschool we swabbed some books and door handles and saw which had the most bacteria. It was surprisingly the books
Answer:
B. electrons possess the largest charge-to-mass ratio among the subatomic particles listed in the four choices.
Explanation:
Consider the mass of each particle. Express the masses in atomic mass units:
- Protons: approximately 1.007 amu each;
- Neutrons: approximately 1.009 amu each;
- Electrons: approximately 0.0005 amu each.
Similarly, consider the charge on each particle. Express the charges in multiples of the fundamental charge:
- Protons: +1 e;
- Neutrons: 0;
- Electrons: -1 e.
Calculate the charge-to-mass ratio for the three species:
- Protons: approximately
; - Neutrons: 0;
- Electrons: approximately
.
Almost all nuclei contain protons and neutrons. The only exception is the hydrogen-1 nucleus, which contains only one proton and no neutron. The mass of the nucleus is approximately the same as the sum of its components' masses. The extra neutron will only add to the mass of the nucleus (the denominator) without contributing to the charge (the numerator.) As a result, the charge-to-mass ratio of nuclei will be positive but no greater than the charge-to-mass ratio of protons.
Among the particles in the four choices, the charge-to-mass ratio is the greatest for electrons.
Answer:
4.61 x 10^23
Explanation: Convert 213g of PbCl2 to mol, which is 0.7658950184462004, multiply 0.765 with 6.022 x 10^23.